Many species of the Myrtle family (Myrtaceae) are popular edibles throughout the tropical and subtropical world. In addition, some are used medicinally in divergent traditional practices from South America to Southeast Asia. The fruits of two species of Eugenia (Myrtaceae) have shown a strong antioxidant activity in the 1,1-diphenyl-2- picrylhydrazyl (DPPH) assay, and subsequent ethnomedical and chemotaxonomic study of related plants in the subtribe Eugeniinae have led to the hypothesis that these fruits contain flavonoids or other polyphenolic compounds that exhibit an oxidative protection to biomolecules in humans. The fruits of ten popular edible species from this taxa will be analyzed for antioxidant activity using the DPPH assay. The most active extracts will be studied in greater detail to isolate and identify specific polyphenolic antioxidant phytochemicals. It is expected that novel antioxidant compounds will be discovered, and their chemical structures will be fully elucidated. This research will then use the analytical tools developed to look closely at beverages and vinegar made from the most active fruit to ascertain whether the beneficial phytochemicals in the fruit can be detected in commercial products.